1. Field of the Invention
The present invention relates to a powder material cartridge that holds a developer (e.g., toner) and that is used in an image forming apparatus including a copying machine, a printer, and facsimile machine. The invention further relates to an image forming section to which the material powder cartridge is attached, and an image forming apparatus that incorporates the image forming section.
2. Description of the Related Art
Image forming apparatuses such as an electrophotographic printer, a copying machine, and a facsimile machine use an electrophotographic image forming process including steps of charging, exposing, developing, transferring, and fixing. A charging roller charges the surface of a photoconductive drum uniformly. An exposing unit employs a light source such as LEDs or a laser, and selectively illuminates the charged surface of the photoconductive drum to form an electrostatic latent image. A developing unit supplies toner to the electrostatic latent image, thereby developing the electrostatic latent image with the toner into a toner image. The toner image is then transferred onto a print medium, and finally fused by a fixing unit into a permanent image. A small amount of toner may remain on the photoconductive drum after transferring the toner image onto the print medium. The residual toner may be removed by a cleaning unit from the photoconductive drum. The residual toner is then transported and is collected as a waste toner into a waste toner collecting chamber.
A toner cartridge includes a fresh toner chamber that holds fresh toner and a waste toner chamber that holds the waste toner. The waste toner chamber includes a waste toner receiving opening through which the waste toner is received from a waste toner transporting unit. The waste toner chamber includes a lid that closes and opens the waste toner receiving opening. The waste toner transporting unit includes a lid that closes and opens the waste toner discharging opening. When the toner cartridge has not been attached to the image forming section of the image forming apparatus, the lid continues to close the waste toner discharging opening, thereby preventing the waste toner from spilling through the waste toner discharging opening of the waste toner transporting unit.
For example, the lid mounted to the waste toner discharging opening on the waste toner transporting unit side and the lid mounted to the waste toner discharging opening on the waste toner chamber side are opened when the toner cartridge is attached to the image forming section, and are closed when the toner cartridge is detached from the image forming section.
When the waste toner chamber holds a large amount of waste toner such that the waste toner piles up near the waste toner receiving opening, the waste toner may accidentally spill on the surrounding components in the image forming section.